Method of fabricating a semiconductor device having a shallow source/drain region

Abstract

A method of fabricating a semiconductor device forms a shallow source/drain region after a deep source/drain region. First, a gate insulating layer including a gate pattern and a gate electrode are formed on a semiconductor substrate. A buffer insulating layer, a first insulating layer, and a second insulating layer are then sequentially formed on the entire surface of the gate pattern and the semiconductor substrate. A first spacer is formed on the first insulating layer at both sidewalls of the gate pattern by etching the second insulating layer. A deep source/drain region is then formed on the semiconductor substrate as aligned by the first spacer. The first spacer is removed. Next, an offset spacer is formed at both sidewalls of the gate pattern by etching the first insulating layer. Finally, a shallow source/drain region is formed on the semiconductor substrate adjacent to the deep source/drain region as aligned by the offset spacer.